Rotary loop-taker mechanism for sewing machines



Nov. 16, 1943. F. PARRY 2,334,644

ROTARY LOOP-TAKER MECHANISMS FOR SEWING MACHINES Filed Nov. 23, 1940 2 Sheets-Sheet 1 F. PARRY 2,334fi4 3 ROTARY HOOP-TAKER MECHANISMS FOR SEWING MACHINES 2 Sheets-Sheet 2 Filed Nov. 23, 1940 Patented Nov. 16, 1943 no'rsnr oor-Tainan. macrramsu For. t

SEWING mcnmss Frank larry, Bridgeport, Conm, mignor to The Elisabeth,

Singer Manuiactnring Oompany,

N. 1., a corporation of New Jersey Application November 23, 19, Serial No. 388,801 g 11 Claims. (oi. 112-250) t h more fully disclosed inthe u. a. patent of w.

This invention relates to-loop-taker mechanisms of sewing machines and, more particularly, to loop-takers of the vertical-axis rotary hook type, and has for an object to provide improved means for supplying lubricant to the actuating mechanism of vertical-axis rotary hooks and to thethread-carrier oscillating mechanism associated therewith.

I The invention also has-for its object to provide means for automatically delivering lubricant in controlled quantity to the thread-carrier raceway of a vertical-axis rotary hook from a substantial supply of lubricant. Other and more specific. objects of the invention will be apparent from the following description and claims.

The invention comprises the devices, combin tions and arrangements of parts hereinafter de scribed in connection with the accompanying drawings, which illustrate a preferred embodiment of the invention and in which:

Fig. l is a front side elevation, partly in ver tical section, of a fragmentary'portion of a sewing machine containing the present improvement. Fig. 2. is a vertical transverse section of the bedplate of the machine on substantially the line 2- -2 of Fig. 1. Fig. 3 is a bottom plan view of a fragmentary portion of the bed-plate of the machine. Fig. 4 is a top plan view of the loop-taker and its supporting bracket. Fig. 5 is a vertical section of the loop-taker supporting bracket on substantiallythe line 5-4 of Fig. 4. Fig. 6 is a horizontal section' of the hook-saddle on sub stantially the line 8-8 of Fig. l.

Referring to the drawings, the sewing machine has a frame including a. work-supporting bed-plate l provided with left and right slideplates H and 12 disposed at opposite sides of. a throat-plate ll suitably secured upon the bedplate ill.

Rotatably journaled in suitable bearings provided at the under side of the bed-plate. II is a horizontally disposed actuating shaft I extending lengthwise of and located at the rearward portion or said bed-plate. Operatively connected 45 to derive work-advancing movements from the actuating shaft i4 is a feed-dog II of the dropfeed type and operating through a suitable teedslot in the throat-plate ii. The feed-dog I is apertured to receive a work penetrating and feeding eye-pointed needle is carried by the lower end of an endwise reciprocatory and laterally vibratory needle-bar I1, the feed-dog I I being opposed by the usual spring-depressed presser-foot Myers. No. 2,128,031, Aug. 23. 1938.

Complemental to the needle I. in the formation of lock-stitches is a rotary loop-taker It of the vertical-axis rotary hook type and having a cup-shaped body provided in .the cylindrical side wall thereof with a thread-loopsfllz beak 20. The cylindrical side wall of the rotary. hook is internally provided with an annular raceway 2|, and iournaled in said raceway is the peripheral bearing-rib 22 or a thread-carrier 23 about which the needle-thread loopsa're cast by the rotary hook. .The thread-carrier is restrained against rotation with the rotary hook in any usual is or suitable manner.

Extending downward centrallytfrom the bottom wall of the rotary hook it, and preferably integral therewith,- is a vertically disposed and tubular hook-shaft 24 having its longitudinal go bore 2! extending throughout the length of the shaft. 111 PI'OVldillB the hook-shait 2. with its longitudinal bore 25, itis preferred to perforate the bottom wall of the hook is andthereaiter to close the perforation by a disk 26 set into a reu cess in the inner face of the bottom wall of the The hook-shaft is i'our'naled in vertically spaced ball-bearings 21 and 28, the upper ballbearing :1 being disposed in proximity to the 30 rotary hook it and in a vertical aperture provided in the substantially horizontal top wall 28 of a'supporting' bracket or hook-saddle Ill. ,Thelower ball-bearing 28 is disposed ina vertical aperture provided in an intermediate horizontal wall 2i spaced vertically from the lower ment by a nut 32 threaded upon the reduced lower end of the'hook-shaft below and adjacent g the lower ball-bearing 28. I

The hook-saddle 20 comprises a chambered casing which houses the actuating mechanism for the rotary hook and for the thread-carrier oscillating device, said casing providing a reservoir containing a supply of lubricant distributed to said actuating mechanism and to the threadcarrierraceway oi the rotary hook. The upper or .top wall 2! of the hook-saddle casing and the bottom wall 32 thereof are integral with a vertical end wall 34, a substantially flat and vertical front side wall II, and with a vertically curved rear side wall 26. The end'portio'n of the hook- The feeding mechanism above referred to saddle casing opposed to the end wall It i closed cured for endwise adjustment by a screw 6!.

by a closure-plate ll detachably secured to the casing by screws, as II; a sealing gasket 39 being preferably interposed between the closureplate 31 and the hook-saddle casing.

The vertical end wall I of the-hook-saddle,

casing has a horizontally apertured lug ll projecting into the chamber of the 'casiu;- 80."; The

end portion ll of a bearing-bushing II in which the actuating shaft is isrotatabiy -Journaled; V The bearing-bushing is secured by a screw i'or endwiseadlustment in a lug 44 depending from the bed-plate l0, and the hook-saddle I! is se-' lug 40 ofthe casing is mounted upon t'liareduced net and for the purpose of slightly oscillating the thread-carrier in a direction opposite to the direction of rotation of the rotary hook.

Disposed in the bore 25 of the tubuiarhookshaft 42 in spaced relation to said shaft is a tom wall 32 of the hook-saddle casing 30. The

supporting plate 69 has a boss H through which cured, upon the end portion ll of the bearingbushing'by a screw 45. Extending from the front sidewall 36 of the hook-saddle ls'a foot 46 of whlchthe rounded upper portion f is secured, by a'screw 41, against a flattened lower face is of a shouldered bearing-lug 4! depending from the bed-plateiil. The screw 41 passes through a slot 50 more foot 48, said slot 50 being elongated leng hwise'of the actuating, shaft [4. Thus, by freeing the -s'crews 43 and l'L-the hook-saddle 30 and the'bearing-bushing 42 may be together adjusted lengthwise of the actuating shaft ll.

Secured by a screw! upon the actuating shaft it, within the hook-saddle casing, is the hub of a spiral driving gear 52. The spiral gear 53 is in driving engagement with a spiral inion 54 secured by a set-screw II n the tubular hookshaft 24 above the lower -bearing '28 therefor. The ratio of the gear I3 and pinion 54 is such that the rotary hook I! performs two rotations for each rotation of the actuatingshaft ii, i. e., for each complete reciprocation of the needle IS. The side face of the driving gear 53 is disposed closely adjacent to an inwardly depressed portion 3'! of thecasing closure-plate 31, and the actuating shaft ll extends through a closely fitting opening in said depressed portion 31' of the closure-plate. The lower portion of the driving gear 53 dips into a supply of lubricant in the bottom portion of the cming, so that said gear throws of! lubricant centrifugally. By 10- cating the depressed portion 3'! of the closureplate in proximity to a side face of the driving gear, said depressed portion 31. of the closureplate serves as a shield which reduces to a minimumthe escape of lubricant through the opening in the closure-plate through which the shaft it extends.

Secured by a screw 58 upon the hook-shaft 24, interiorly of the casing 30 and between the spiral pinion 54 and the upper hook-shaft bearing .21, is the hub of an eccentric i1; and embracing the eccentric 51 is the strap of a short horizontally disposed pitman 58. The pitman 58 is apertured to receive a pivot-stud 59 extending vertically from a crank-arm 60 having a split boss clamped upon the lower end of a vertically disposed rockshaft 62. The rock-shaft 62 is Journaled .for oscillation in the top wall 28 of the hook-saddle 30, and the upper end of the rock-shaft 62 is provided with a carrier-arm 63 disposed exterior- 1y of the casing 30 and having a horizontal portion thereof located between the top wall 29 of the casing and the rotary hook". The carrierarm 63 is bent upwardly between its ends and, terminates in an enlargement which ishorizontally recessed in its upper face, adjacent the rim of the rotary hook ii, to receive the shank of a horizontally disposed opener-finger Sits free end of the opener-finger is positioned to engage the thread-carrier 23 in the usual manthe tube 61 extends, said boss Ii being disposed in an aperture 12 in the bottom wall 32 of the casing. A sealing gasket 13 is preferably disposed between the plate 68 and the bottom wall 32 of the casing.

The tube-supporting plate 69 is provided with a horizontal aperture 14 having one end thereof terminating in the vertical tube aperture of said plate in alinement with a radial aperture provided in the tube 61. Disposed in'the supporting-plate aperture I4 and extending upwardly through the tube 61 into engagement with the closure disk 26 in the bottom wall of the rotary hook I9 is a lubricant-conducting wick 1.5. The bottom wall of the rotary hook is has a radial and preferably wick-filled duct 16 extending outwardly from the axial opening in the bottom wall of the rotary hook, i. e., from the bore of the hook-shaft 24, said radial duct 16 being connected with the lower end of a vertical duct H which is also preferably wick-filled and extends to the hook raceway 2i in a direction sub stantially parallel to the axis of rotation of the rotary hook,

Theinner wall of the hook-saddle casing is recessed to provide a horizontally fiat shelf 18 comprising a continuation of the upper face of the intermediate bearing-wall 3 I. the shelf 18 is formed with an upwardly open pocket 19, and opening into the bottom wall of said pocket is the upper end of a vertically inclinedduct 80 provided in the wall of the casing 30. The lower end of the duct I0 is connected by alined apertures provided in the sealing gasket l3 and supporting-plate 69 with the supporting-plate aperture 14. A lubricant feeding wick 8! is preferably disposed in the duct It, the lower end of said wick 8i contacting the wick 15.

The shelf-pocket 19 is filled with a lubricantabsorbent packing 82, such as felt or the like, and it is preferred to have the felt-packing 82 extend above the upper'face of the shelf 18. Bearing downwardlyupon :the felt-packing to compress and thereby control the porosity thereof is the flanged lower end of a regulator 82 havingat its upper end an enlarged head 84 threaded into the top wall 29 of the hook-saddlecasirig 30. The slotted upper end of the regulator-head 84 is accessible exteriorly of the casing 20 for varying the density and therefore the porosity of the felt-packing 82.

As illustrated more particularly in Pig. -6 of the drawings, the casing wall from which the intermediate bearing-wall 3| extends is formed with a recess 85 of which the bottom wall is substantiallylevel with the inner face of the bottom wall 32 of the hook-saddle-casing. Disposed in said recess 85 is a lubricant-measuring rod 86 having its lower end resting upon the bottom wall of the recess. The measuring rod 88 extends through an aperture in the shelf-wall it and the upper end of the measuring rod extends through and is rounded to closely fit a filling aperture 81 in The wall of the top wall 29 of the hook-saddle casing. By

:removingthe -rod 8 6, the casing may be supplied with lubricant through the casing-aperture 81. It will'be understood fromthe foregoing de- :wherebythe upper compartment 88 is open from the-front=portion-ofthe casing to the rearward portion thereof which houses thedriving gear 53'." However-, the lower front compartment 89 of the casingis also connected with the rearward portion ofrtheupper compartment 88 by a passageway 90 adiacent the closure-plate 31.

.As indicated by' the dot-dash line in Fig. 2 of the drawings, suflicient lubricant is preferably supplied to the hooksaddle casing, through the posed in the bore of said shaft, lubricant-conducting connections between the bore of said shaft and said raceway, and means including a lubricant-delivery regulating device for supplying lubricant to the wick of said tube.

2. In a sewing machine, a vertically reciprocatory needle, a vertical-axis rotary loop-taker complemental to said needle in the formation of lock-stitches and provided with a thread carrier raceway, a vertically disposed loop-taker carrying shaft having a longitudinal bore, a wick-filledtube extending lengthwise of and dis posed inthe'bore of said shaft, lubricant-conducting connections between the bore of said shaft and said raceway, and means including a manually regulatable metering device disposed above thelower end of said shaft for supplying lubricant in the wick of said. tube.

filling: aperture flhtobring the level of the 111- bricant substantially up to the lower face of the wardly through the lower ball-bearing 28 and a through theapassageway 90, whereby the level of the lubricant in the compartment 89 may be measured. qThefelt-packing 82 functions as an oil-:meteringdevice to supply lubricant to the wick 80.: In this manner, lubricant is supplied to the wickl5 and is fed by capillarity to the endzofthe wick liadjacent the bottom wall of therotaryihook. The lubricant is thrown off from'theupperiend of the wick I5 by the rotary hookand 'isthus supplied to the radial duct 16 oftherotaryhook and delivered to the rotary hook raceway 2|. Excess lubricant delivered by the upper nd of the wick may drain downwardly through the bore of the hook-shaft 24, externally of the stationarytube 61.

In order to obviate feeding of lubricant from the casing compartment 89 upwardly to the looptaker .through the bore of the hook-shaft 24, by the ,rotation'of the shaft about the stationary tube 61, saidtubeis preferably provided with a radial aperture open to a diametral duct in the driven pinion secured upon the hook-shaft. The rotary hookshaft 24 and the hub of the eccentric 51 are also preferably provided with additionalducts leading to the outer face of the eccentric. The outer walls of the casing are preferably. provided with threaded apertures loeated to affordaccess'to the securing screws of the actuating mechanism within the casing, said apertures being normally closed by suitable 1 screws whereby the chamber of the casing is substantially oil-tight.

Having thus set forth the nature of the invention, what I claim herein is:

1. In a sewing machine, a vertically reciprocatory needle, a vertical-axis rotary loop-taker complemental to said needle in the formation of lock-stitches and provided-with a thread-carrier raceway, a vertically disposed loop-taker carrying shaft having a longitudinal bore, a wick-filled 3. In a sewing machine, a, vertically reciprocatoryneedle, a vertical-axis rotary loop-taker complemental to said needle in the formation of lock-stitches and provided with a thread-car rier raceway, a loop-taker bracket having a chambered casing providing a lubricant-supply reser voir, a vertically disposed loop-taker shaft rotatably lournaled in said bracket and provided with a longitudinal bore having lubricanteconducting connections with said raceway, a tube extending froma wall of said bracket into the bore of said shaft, a lubricant-conducting wick extending lengthwise in the bore of said shaft and disposed in said tube, and means including a lubricant-collecting'f device disposed above the level of the supply of lubricant in said reservoir for feedinglubricant to said wick.

4. In a sewing machine, a vertically reciprocatory needle, 9. vertical-axis rotary loop-taker complemental to said needle in the formation of lock-stitches and provided with a thread-carrier raceway, a chambered casing providing a lubricant-supply reservoir, a vertically disposed looptaker shaft rotatably journaled in said casing and provided with a longitudinal bore having lubricant-conducting connections with said raceway, a shelf-wall disposed in the chamber of said casing and provided with a lubricant-pocket disposed above the level of the supply of lubricant in said reservoir, a lubricant-metering device disposed in said pocket, means disposed in said casing for supplying a flood of lubricant from said reservoir to said pocket, and means for conducting lubricant delivered by said metering device through the bore of said shaft.

5. In a. sewing machine, a vertically reciprocatory needle, a vertical-axis rotary loop-taker complemental to said needle in the formation of lock-stitches and having a thread-carrier raceway, a chambered casing having an internal bearing-wall disposed above the bottom wall of said casing in vertically spaced relation thereto and providing a lubricant-reservoir between saidwalls, said internal wall being provided in its upper face with a lubricant-pocket, a vertically disposed loop-taker carrying shaft iournaled in said bearing wall with the lower end of said shaft spaced from the bottom wall of said casing, said shaft being provided with a longitudinal bore having lubricant-conducting connections with said raceway, a lubricant-metering device dis posed in said lubricant-pocket, means disposed within said casing for supplying a flood of lubri= cant to said metering device, and lubricant-conducting connections with said metering device for stationary tube extending lengthwise of and dis- 1; feeding lubricant through the bore of said shaft.

In a sewing machines, vertically reciprocatory needle, a vertical-axis rotary loop-taker complemental to said needle in the formation of lock-stitches and having a thread-carrier raceway, a chambered casing having an internal bearing-wall disposed above the bottom wall of 3 said casing in spaced relation thereto and pro- ,viding a lubricant-reservoir between said walls, said internal wall being provided in its upper face with a lubricant-pocket, a vertically disposed loop-taker carrying shaft iournaled in said bearing wall with the lower end of said shaft spaced vertically from the bottom wall of said casing.

bered casing providing a lubricant-supply reservoir, a vertically disposed loop-taker carrying shaft rotatably joumaled in said casing and provided with a longitudinal bore having lubricantconclucting connections with said raceway, a wick-filled tube extending upwardly from the bottom wall of said casing and lengthwiseinto the bore of said shaft, and means rendered effective by a moving part of the machine within said casing for delivering lubricant from a supply in said reservoir to the wick within said tube.

8, In a sewing machine, a vertically reciprocatory needle, a rotary loop-taker complemental to said needle in the formation of lock-stitches and having a thread-carrier raceway, a chambered casing providing a lubricant-supply reservoir, a vertically disposed loop-taker carrying shaft rotatably Journaled in said casing and provided with a longitudinal bore having lubricant-con ducting connections with said raceway, means for rotating said shaft including driving and driven gears housed by said casing within the lubricantsupply reservoir thereof, a plate detachably secured to the bottom wall of said casing, a wickadapted to dip into the supply of lubricant in said reservoir, a lubricant-collecting device disposed in said chamber above the level of the supply of lubricant therein and below said loop-taker, and means for feeding lubricant from said lubricantcollglecting device to said be torn wall of the loopta er.

10. In a sewing machine, a supporting bracket having a housing chamber providing a lubricantsupply reservoir, a rotary loop-taker shaft Journaled in said bracket for rotation about a vertical axis, a loop-taker carried by the upper end of said shaft and having a thread-carrier raceway. said shaft having a longitudinal bore and said loop-taker having a lubricant duct connecting said shaft bore with said raceway, a loop-taker actuating shaft iournaled for'rotatlon about an axis transverse to the axis of rotation of said loop-taker shaft, driving connections in said chamber between said shafts including a toothed gear adapted. to dip into the supplyof lubricant in said reservoir, a lubricant-collecting device disposed in said chamber above the level of the supply of lubricant therein and below said looptaker, and means for feeding lubricant from said collecting'device into said shaft bore endwise of the shaft and upwardly through said bore.

11. Aloop-takermechanism for sewing machines, comprising, a chambered casing providing a lubricant-supply reservoir, a vertically disposed loop-taker shaft, vertically spaced bearings in said casing for said shaft, a loop-taker carried bythe upper end of said shaft externallylof said casing, said loop-taker having a body provided with a thread-carrier raceway, a thread-carrier journaled in said raceway and restrained against rotation with said loop-taker, means for rotating said shaft including driving and driven gears disposed in the chamber of said casing, one of said gears being disposed to dip into a supply of lubrifilled tube extending upwardly from said plate and lengthwise into the bore of said shaft, and means for delivering lubricant from a supply in said reservoir to the wick within said tube.

9. In a sewing machine, a supporting bracket having a housing chamber providing a lubricantsupply reservoir, a rotary loop-taker shaft journaled in said bracket for rotation about a vertical axis, a loop-taker carried by the upper end of said shaft and including a body having a side cant in said reservoir, an eccentric carried by said shaft in the chamber of said casing and between said bearings, a vibratory finger disposed externally of said casing for oscillating said thread-carrier in a direction opposite to the direction of rotation of said loop-taker, a rockshaft iournaled in said casing and carrying said finger, and operative connections with said eccentric within said chamber of the casing for actuating said rock-shaft.

- FRANK PARRY. 

